1. Field of the Invention
This invention relates to an antenna interface and a method of unifying the elements thereof and more particularly, it relates to a broadband direction finding antenna interface wherein the components are so connected that the upper most operating frequency can exceed forty gigahertz.
2. Description of the Prior Art
Previous to this invention, the radio frequency detected by the direction finding antenna was transformed at each antenna arm termination to a semirigid coaxial transmission line and thereafter to an arithmetic network where appropriate signal processing occurred before the signal was sent to the guidance control system. Both the antenna arms and the arithmetic network were constructed of strip transmission lines (striplines). This resulted in two stripline-to-coaxial interfaces per antenna arm. Because of fabricating limitations, the phase and amplitude matching of coaxial lines, stripline-to-coaxial transitions, and coaxial connections constrained the operating frequencies to those below eighteen gigahertz.